On a personal level you could reduce contrast / brightness on your monitor.
Re the UX question there are numerous studies regarding reading legibility. Early screen designs had far less contrast than we have today. There are many great articles on the subject. One article well worth reading would be:
The Impact of Web Page Text-Background Color Combinations on Readability,
Retention, Aesthetics, and Behavioral Intention
The purpose of this experiment was to examine the effect of web page
text/background color combination on readability, retention, aesthetics,
and behavioral intention.
The above article goes deeply into background/text contrast and reviews.
Due to the contrast effect one would expect that a white background would result in better readability. Therefore, [the authors] replicated the method of the first experiment with the exception that only black text and three different background colors (light gray, dark gray, and white) were used.
Surprisingly, they found better performance with the gray backgrounds than with the white background, a finding, again, inconsistent with the contrast effect.
(Ironically, despite these findings, the default background in web
browsers these days is, of course, white.)
The difference in contrast has a lot to do with studies between reading on paper and monitors.
Before 1992 most studies concluded that people read slower, less accurately and less comprehensively on screens than on paper. Studies published since the early 1990s, however, have produced more inconsistent results
There is a problem in studying the differences (reading paper and screen) and that has to do that the quality of monitors is improving exponentially. The quality of monitors today (as regards DPI, refresh rate, color rendering) is miles ahead of that available in the 1980s and 1990s.